Discussion: Ceramic namespace in JSON schemas

[PaulLeCam]

---

cip: 88
title: Ceramic namespace in JSON schemas
author: Paul Le Cam (@PaulLeCam)
status: Draft
category: Standards
type: RFC
created: 2021-03-01

Simple Summary

Define a standard extension point for Ceramic-specific metadata in a JSON schema.

Abstract

This CIP defines a reserved namespace for Ceramic-specific metadata in a JSON schema, along with a reference table for standard uses of this namespace.

Motivation

As commented in #82 (comment) the $id cannot be used to define Ceramic-specific extensions as intended in CIP-82, so creating a custom namespace for Ceramic-specific metadata should be a safer option to enable further extensions.

Specification

Namespace

A JSON schema property can contain a $ceramic field, that must be an object with a unique type defined in the following reference table, for example:

{
  type: 'string',
  maxLength: 150,
  $ceramic: {
    type: 'tile',
    schema: '<schema docID or commitID>' ,
  },
}

Reference table

Type	CIP	Status
tile	DocID json-schema definition	Draft

Rationale

Using the $ceramic property should be consistent with other $-prefixed metadata properties in JSON schemas, avoiding possible conflicts with other property names.

A unique type, along with possible type-specific additional properties, should make it easy to add custom extensions and build tools (simple checks for existence of $ceramic property and type-specific logic, TypeScript interfaces and inference, etc.).

Finally, providing a reference table in this CIP should allow for easy discovery and avoid conflicts between extensions.

Backwards Compatibility

CIP-82 and CIP-85 will get updated to this new format.

Implementation

None yet.

Security Considerations

None I'm aware of.

Copyright

Copyright and related rights waived via CC0.